1. Field of the Invention
The present invention relates to a line-contact dry electrode, particularly to a comb-like line-contact dry electrode.
2. Description of the Related Art
In recent years, electro-biomedical signal measurement devices, which can detect physiological signals from skin, have been extensively used in medical diagnosis and research, including electrocardiography (ECG), electroencephalography (EEG), electromyography (EMG), galvanic skin reflex (GSR), and body fat meters. The electro-biomedical signal measurement devices are non-invasive detectors. For an example, EEG can record brainwaves and features economy, safety, easy operation, and comfortable inspection environment. Therefore, EEG has been widely used in clinic diagnosis and neurobiological research, such as inspections for patients of coma, apoplexy, epilepsy, encephalitis, Parkinson's disease, and other brain diseases.
The sensor electrodes used by EEG may be categorized into the wet electrodes and the dry electrodes. While the wet electrode is used, the testee's skin normally needs processing beforehand, such as removing the horny layer or shaving the hair-rich region, so as to overcome too high interface impedance between the skin and the electrode. Further, conductive paste is applied to the testee's skin to achieve better measurement quality. With time elapsed, the conductive paste will dry, and its conductivity will decay. Therefore, the conductive paste needs applying to the testee's skin repeatedly, which not only may irritate the testee's skin but also makes the operation complicated and time-consuming. The dry electrode is fabricated with a microelectromechanical technology and less likely to damage in measurement. The dry electrode normally uses a flat probe module to contact the testee's skin and detect the physiological signals without using any conductive paste. The dry electrode can directly contact the skin of a hair-rich region, e.g. the head skin. The dry electrode outperforms the wet electrode in some respects. However, the flat probe module is unlikely to comply with the contour of the head. Further, hair is likely to interfere with measurement and affect the precision thereof. Thus, the dry electrode can not effectively work in EEG, which is undertaken on the head. Therefore, how to decrease the discomfort the dry electrode causes to testees and increase the precision of measurement using the dry electrode is a problem the field concerned is eager to overcome.